Análise da toxicidade de água de rio contaminada com herbicida ametrina utilizando colunas de Winogradsky e microalgas como bioindicadoras

• Autor(a) principal: Santos, Ana Carolina dos [UNESP]
• Data de Publicação: 2016
• Tipo de documento: Trabalho de conclusão de curso
• Idioma: por
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://hdl.handle.net/11449/155821; http://www.athena.biblioteca.unesp.br/exlibris/bd/capelo/2017-08-30/000889851.pdf
• topic: Ecologia aquatica; Herbicidas; Ecossistemas aquáticos; Microalga; Água - Poluição; Ribeirão Claro, Bacia (SP); Rio Claro (SP)

Ametryne is a herbicide widely used for combating weeds in production of sugar cane, corn, coffee, among others, persistent, toxic, capable of reaching groundwater and be carried into the rivers. Capable of inhibiting photosynthesis, which may disturb the growth of algae. The objective of the study was to analyze an aquatic ecosystem contaminated with herbicide ametryne. Therefore, were collected water and sediment of Ribeirão Claro (tributary of the Rio Corumbataí) in Treatment Plant 1 ( ETA 1) DAAE the city of Rio Claro- SP to prepare 8 Winogradsky columns for monitoring algae. The tests contained four volumes of the herbicide, at concentrations 3.75 g.L-1 (0 uL, 100 uL, 250 uL, and 500 uL of ametryne) in duplicate (trials A and B) .The algae were identified by light microscopy, the cells of algae counted weekly by Neubauer chamber. For phytotoxicity was used 20 seeds of Lactuca/ plate containing sterile and moistened paper filter with 3 mL of water from the column, the plates were incubated for 120 hours at 20° C was measured root growth of the seeds. Conductivity anh pHs readings were taken after weekly of the columns. The algal biomass was quantified by determining the chlorophyll a by spectrophotometer. There was alteration in the species found in columns with different volumes of ametryne, besides decrease in the number of algae cells, changes in pH and conductivity, besides presenting phytotoxicity to seeds of lettuce and reduced biomass. The herbicidal toxicity presents ametryne microalgae